In my K2-SE-VeryBZ 10x game have/had a sandbox where it turned out to be burning 15 UPS doing seemingly nothing. A few arcospheres were being shuffled between boxes by bots but if I reset the sandbox, instantly I am back to 58-60 ups. Prior to reseting I'd been assuming that this was just as good as it gets for UPS for this game.

VERY interestingly, if I delete the whole contents of the sandbox I continue to lose 15 UPS. Yes, a sandbox, NOT reset, just everything deleted and I get a 15 UPS penalty.

The floor isn't entirely clean though. There are a few undeletable things like:
- tiles such as whatever undeletable thing that waterfill turns into
- the "dark grey ground" tile that pasting a BP that includes scaffolding turns into.
- Reactor interfaces that seem to stay as entities on the map even after reactors are deleted. Not visable but show on map and have a "mouseover" popup

Clicking reset on this sandbox takes me from steady 45 UPS to 58-60 almost instantly.

I've preserved a save if anyone is interested.

I'm interested in getting the save to see if I can profile it more.

I'm interested in getting the save to see if I can profile it more.

Whats the best way to send it to you?
2 saves:
- one before deconstructing the contents with UPS hit
- one after deconstructing the contents with UPS hit still there

https://drive.google.com/drive/folders/1tVCPDG_fhQHBQzIgHOJztWxYwUbz8pQ5?usp=sharing

I'd be zero % surprised to find out its a misbehaving ReactorInterface or some such. I should dump that addon as it doesnt work as I'd hoped for AntiMatter Reactors

There also seemed to be an oddity where there is a discrepancy between "entity update" (14ish) on the show-time-usage page and the total on the show-entity-time-usage page(8ish). As if some entity was burning time while not showing up in the entity-time-usage printout.

Catch me on Earendel's Se Discord in the K2SE channel.

Well, I spent a bit on your world, and I found something more specific that recovered basically 95%+ of the lost UPS from that Sandbox: pollution. I can recover 16 UPS from clearing all pollution in that Sandbox, compared to 17 by resetting it. I have the red pollution overlay turned on for the map, so I quickly noticed how super red it was in there, but I was surprised to find that hunch paid off!

So, I don't think it's any particular mod that is causing problems or not cleaning up after itself - although it is weird to have some "leftovers" that cannot be deleted. If you're comfy with console commands, it was easy to remove all of it. If not, K2 has air purifiers, so you could handle it "naturally." I'm also curious if you think that "cleaning up" the pollution as a setting in this mod would be beneficial, and if so, what sort of setting. Like, always removing all pollution? Removing any beyond a perimeter? My best guess for the performance hit is that the pollution travels very far and requires a ton of extra chunks to be processed every tick.

Well, I spent a bit on your world, and I found something more specific that recovered basically 95%+ of the lost UPS from that Sandbox: pollution. I can recover 16 UPS from clearing all pollution in that Sandbox, compared to 17 by resetting it. I have the red pollution overlay turned on for the map, so I quickly noticed how super red it was in there, but I was surprised to find that hunch paid off!

So interesting!!

Interesting! Does the default sandbox terrain have zero pollution absorption and infinite size? I can see that being problematic for sure.

If that is the case it is also GENERATING all of the chunks to track pollution spread too, increasing save file size and memory footprint.

Ideas:
- Include setting a high pollution absorption on the default terrain like open space does in SE (look at pollution in orbit in my Nauvis Orbit, pollution spreads across scaffolding but even a thin "moat" of empty space between tiles prevents spread because the black "empty" space has high absorption). If the player places a different surface tile then the absorption properties of that could override but beyond where they've placed their own dirt tiles, high absorption.

• Copy the functionality from https://mods.factorio.com/mod/se-little-inferno where pollution does not spread on biter-less surfaces. What is the point of polution tracking on a surface without biters?

I think setting high absorption on your black background tiles in all sandboxes would be the easiest fix though.

The latest release attempts a solution. Before, by default, Lab Tiles did not absorb pollution. Now, a new setting, enabled by default, adds a fairly large amount of absorption to them. It's not perfect, because there are basically limits to how much each chunk/tile can absorb, and it's fairly low. That said, it's basically like having a grass-filled chunk, so it will definitely curb the expansion.

I actually don't know how SE is "eliminating" the pollution for space tiles. I would like to do something like that, but I have a feeling that there's something "special" about the lab tiles from the core game that are preventing me from doing certain things with them.

Interesting... I asked about it once and its just that SE space tiles have a HIGH absorbtion. Or so I was told.